Tutorial quote: Mary, the daughter of a friend is in college: her Windows XP laptop constantly reboots and, we suspect, has a bad hard drive. The system will boot a live CD (Ubuntu 9.10 Karmic Koala Desktop), and data on the hard drive can be read. During boot, the live CD identifies disk errors and tries unsuccessfully to repair them.

Tutorial quote: This article describes how you can back up MySQL databases without interrupting the MySQL service. Normally, when you want to create a MySQL backup, you either have to stop MySQL or issue a read lock on your MySQL tables in order to get a correct backup; if you do not do it this way, you can end up with an inconsistent backup. To get consistent backups without interrupting MySQL, I use a little trick: I replicate my MySQL database to a second MySQL server, and on the second MySQL server I use a cron job that creates regular backups of the replicated database.

Tutorial quote: Do you suspect that you have a compromised system ?
Check now for root kits that the intruder may have installed !!!

So... What in the hell is a root kit ???
A root kit is a collection of programs that intruders often install after they have compromised the root account of a system.
These programs will help the intruders clean up their tracks, as well as provide access back into the system.
Root kits will sometimes leave processes running so that the intruder can come back easily and without the system administrator's knowledge !

Solution....
Scripts like chkrootkit will do the job for you automatically.

Tutorial quote: There's been a lot of talk lately about encrypted partitions, and Debian is proud to offer a feature to easily create them in the etch installer since beta3. But what about existing systems? This guide walks you through setting up an encrypted partition using cryptsetup and LUKS.

Tutorial quote: Last time we introduced a few common Linux filesystems and examined their features. If you've already installed Linux, your partitions are already set up and configured with particular filesystems, but you may decide you want to modify this configuration. What's the best way to begin?

Tutorial quote: The cpio command is one of the most commonly used Linux back up tools.

The cpio command has two unusual features

Unlike tar , in which the files to back up are typed in as part of the command, cpio reads the files to work with from the standard input (in other words, the screen).

This feature means that cpio must be used as part of a multiple command or with a redirection pipe. Examples of this usage are shown in the tables below.

cpio must always be used with one of three flags. Flags are options that set the mode in which the command runs. Only one flag can be used at a time, and it must come before any other options. In addition, the choice of flags limits the options that can be used. Each flag also has a gnu option that can used in its place. The gnu option gives a convenient name for each flag: extract, create, and pass- through.

Tutorial quote: This document describes a method for generating automatic rotating "snapshot"-style backups on a Unix-based system, with specific examples drawn from the author's GNU/Linux experience. Snapshot backups are a feature of some high-end industrial file servers; they create the illusion of multiple, full backups per day without the space or processing overhead. All of the snapshots are read-only, and are accessible directly by users as special system directories. It is often possible to store several hours, days, and even weeks' worth of snapshots with slightly more than 2x storage. This method, while not as space-efficient as some of the proprietary technologies (which, using special copy-on-write filesystems, can operate on slightly more than 1x storage), makes use of only standard file utilities and the common rsync program, which is installed by default on most Linux distributions. Properly configured, the method can also protect against hard disk failure, root compromises, or even back up a network of heterogeneous desktops automatically.

Tutorial quote: Mirror setup. Recently I was given a brand new X2100 server made by Sun Microsystems. I installed FreeBSD on it and run a mailserver. The server has two 250GB SATA drives and I decided to use gmirror(8) to create RAID-1 on those disks.